The difference between Add up and Tally

When used as verbs, add up means to take a sum, whereas tally means to count something.

Tally is also interjection with the meaning: target sighted.

Tally is also noun with the meaning: originally, a piece of wood on which notches or scores were cut, as the marks of number.

Tally is also adverb with the meaning: in a tall way.

check bellow for the other definitions of Add up and Tally

Add up as a verb (transitive):

To take a sum.

Examples:

"usex Add up the prices and find out how much it will cost."
Add up as a verb (intransitive):

To accumulate; to amount to.

Examples:

"usex If you can save even a couple of dollars per day, it will add up to a lot over a year."
Add up as a verb (idiomatic, intransitive):

To make sense; to be reasonable or consistent.

Examples:

"usex His story just doesn't add up. Why would he have been at the restaurant the day before the event?"

Tally as a noun:

Originally, a piece of wood on which notches or scores were cut, as the marks of number
Tally as a noun:

Later, one of two books, sheets of paper, etc., on which corresponding accounts were kept.
Tally as a noun:

Hence, any account or score kept by notches or marks, whether on wood or paper, or in a book, especially one kept in duplicate.
Tally as a noun:

One thing made to suit another; a match; a mate.
Tally as a noun:

A notch, mark, or score made on or in a tally; as, to make or earn a score or tally in a game.
Tally as a noun:

A tally shop.
Tally as a noun:

A ribbon on a sailor's cap bearing the name of the ship or the (part of) the navy to which they belong.
Tally as a noun (informal, regional, dated):

A state of cohabitation, living with another individual in an intimate relationship outside of marriage.

Tally as a verb (transitive):

To count something.
Tally as a verb (transitive):

To record something by making marks.
Tally as a verb (transitive):

To make things correspond or agree with each other.
Tally as a verb (intransitive):

To keep score.
Tally as a verb (intransitive):

To correspond or agree.
Tally as a verb (nautical):

To check off, as parcels of freight going inboard or outboard.